Dispute cancellation

I will never recommend my family and friends to *********** like cellc customerserviceagent , never , I only noticed now recently that ripped me off mother's Airtime ,Dms and Data that curried over she never used and was already paid previously when contract cancelled, what was reason behind taking that. The crucial issue is wrong number was cancelled no one is taking accountability of the mistake and claims is in error for what exactly , I have spoken to 4 cellc media agents that **** and promised they will come back to me with response and they dissappeared . the Airtime ,Sms and the Data that cellc ripped me off is more that what they claimed I owe them , I will continue engaging till get responses . Someone from cellc think I am stupid .